Gas fired room heaters and decorative gas fireplace logs are in use in commercial and residential applications in large numbers. Many of these appliances are remotely controlled. These remotely controlled appliances utilize thermocouples and thermopiles to generate singular EMF signals to energize safety devices and activate remote control circuitry. A pilot flame or burner flame in contact with the thermocouple and thermopile generates the EMF signals required by each device via the Peltier heating and cooling effect. Typically at least one thermopile and one thermocouple are mounted to a pilot bracket or gas burner. Newer controls require more than one thermopile mounted to the pilot bracket or gas burner. As the number of EMF generators required to operate the number of control devices increases so does the physical size of the pilot assembly or gas burner bracket. Likewise, as the thermopile device grows in physical size in order to generate an EMF signal sufficient to activate the control devices so does the amount of energy required to generate a flame substantial enough to heat the generators. In addition as the mass of the thermopile increases so does the length of time required to generate the required EMF signal or to dissipate heat fast enough to deactivate the safety control devices connected to them creating potentially hazardous conditions.
The primary object of this invention is to provide a combined thermocouple and thermopile EMF generator capable of producing multiple EMF signals in one unit.
A further object is to provide an improved space factor, that is to provide a smaller pilot or burner gas bracket with a combined thermocouple and thermopile that is capable of generating multiple EMF signals.
A further object is to minimize the number of thermopiles necessary to supply the required EMF signals by utilizing one thermopile to generate primarily two signals although more signals may be generated.
A further object of this invention is to provide multiple EMF signals from one device.
A further object is to provide an improved response time by isolating the combined thermocouple of lesser mass from the thermopile of greater mass.
A further object is to provide a thermocouple and thermopile construction wherein a thermocouple of a construction commonly know to the industry is longitudinally centered within a thermopile of commonly know construction.
A further object is to provide a thermopile and thermocouple construction wherein the conductors of the thermopile are comprised of dissimilar metals joined at each end to form hot and cold junctions, arrayed in a circle and enclosed in a metal sleeve or jacket; and a thermocouple assembly comprised of a standard ferric chrome, nickel chrome or inconel tip; a constantan wire longitudinally centered within and permanently connected to the tip and an insulated copper wire permanently affixed to the outside of the tip. The thermocouple assembly being longitudinally centered within and isolated from the metallic sleeve and thermopile array contained within a metallic sleeve.
A further object of the invention is to provide a thermopile construction wherein wire extension leads connected to cold junctions at each single metal strip at either end of the array provide one EMF signal and one wire extension connected to a cold junction at an intermediate position providing a second EMF signal are arrayed in a circle and enclosed in a metal sleeve or jacket. A thermocouple assembly longitudinally centered within and isolated from the thermopile array contained within a metallic sleeve or jacket adds an EMF of lesser potential thus providing a total of three EMF signals from the combined thermocouple and thermopile.
Yet another object of this invention is to provide such a combined thermocouple and thermopile that is easy to manufacture, sturdy in use, and easy to assemble.
Other objects and advantages and features of this invention will become apparent from the following detailed description and annexed drawings.
In accordance with the principles of this invention, the above objects are accomplished by providing a combined thermocouple and thermopile as summarized in the abstract. A thermopile comprised of dissimilar metals joined at each end to form hot and cold junctions are arrayed in a circle and enclosed in a metal sleeve or jacket. The thermocouple array of which the thermopile is comprised, is capable of delivering at least two EMF signals. A thermocouple constructed of a tip, a constantan wire and a copper wire lead which is centrally located within the thermopile assembly, with the tip located at the hot junction end and isolated from the metallic sleeve and thermopile array. The combined thermocouple and thermopile provides at least three EMF signals, occupies less space and improves response time when in the presence or absence of a flame.